The invention relates to an apparatus for pressure gasification of a finely divided combustible material.
A gasification apparatus for a pressure gasification is known including a gasification reactor, a quenching pipe for crude gas issuing from the gasification reactor and a convection-heated boiler with convection heating surface elements for receiving the heat from the crude gas.
Finely divided combustible material means fine grained to dust-like combustible material. Particularly this material can be a fuel such as coal. The energy is supplied to the gasification reactor by burner, which also entrains predominantly the finely divided combustible material. The gasification reaction is controlled in regard to thermodynamic considerations so that a commercially useful gas of a predetermined composition is produced. Reactions are frozen, so to speak, in the quenching pipe by chilling. Furthermore a quenching gas is admitted to the quenching pipe. The expression "gas" also mean "vapor" in the scope of the present invention. The invention provides apparatus for a pressure gasification of finely divided combustible material in a single stage.
In a gasification apparatus of the above-described type the walls of the gasification reactor, the quenching pipe and the convection-heated boiler and other components are provided with pipe walls made from welded parallel pipes or with pipes for the purpose of high-temperature liquid cooling, e.g. in the form of boiling water cooling. This is also true in the apparatus according to the invention. It is understood that the heat received by the pipe walls is utilized in the process performed in the apparatus.
In the known gasification apparatus, on which the invention is based and which is described in European Patent Document 0 115 094 A2, the gasification apparatus includes a first tower-like structure in a first pressurized vessel containing a gasification reactor with a quenching pipe. Behind the quenching zone the quenching pipe acts as a radiant heat boiler and can be provided with corresponding heat radiating surfaces. The convection boiler is formed by a second tower-like structure in a second pressurized vessel. The pressurized vessel can be cooled. Both tower-like structures are connected at their top ends by a cooled connecting duct, through which a crude gas issues from the quenching pipe or radiant heat boiler into the convection-heated boiler. The connecting duct is designed as a thermal expansion compensating device or is provided with such a device. That is expensive and requires expensive features for feeding and delivering quenching gas and heat carriers in the pipe walls of the quenching pipe, the radiant heat boiler and the convection-heated boiler. The apparatus is divided into two structures because of thermodynamic reasons, while the apparatus in both structures operates at different temperature ranges and different thermal expansions. As a result a comparatively large structural volume with suitable mass is required for a certain output of commercial gas produced. The structural volume/output relationship of the prior art required considerable improvement.